Use of bracing between joists in floor construction is well known. One objective of bracing is to prevent joists from moving out of a square alignment with the floorboards they are supporting. Without bracing, joists may rotate about a horizontal axis resulting in floors that "squeak" due to a gap developing between the bottom of the floorboard and the non-horizontal surface of the joist. Bracing also strengthens the overall joist structure by distributing the load between joists.
A wide variety of bracing systems have been utilized, the traditional and most common being a pair of wooden members arranged in an X-pattern between a pair of joists. Such a brace system does not produce a consistently strong product, as the quality of wood for each brace may vary considerably. Wood braces have a tendency to warp as they dry, thus moving from their optimal support position. Further, the nailing of wood braces to joists can result in splitting of the brace where it is nailed to the joist, thus reducing structural strength.
Although various building regulations exist to specify the distance between floor joists, these regulations are not always adhered to. To reduce costs in a building that does not require standard spaced floor joists, fewer joists are installed resulting in a greater distance between joists. In addition, errors in construction can result in joists not being consistently spaced. Braces of fixed length will not support joists that are separated by variant lengths.
U.S. Pat. No. 457,664 discloses steel crossbraces designed to fit over the tops and bottoms of joists and to be adjustably connected by a nut and bolt. Such a brace requires that the bracing be installed before the floor is laid and will raise the floor above the joists in the area where the floor contacts the brace. In order to provide a level, squeak resistant floor, the installer must add material to the joists between the braces or recess the floor where it contacts the braces.
U.S. Pat. Nos. 3,077,009 and 3,102,306 disclose an adjustable brace and a method for manufacturing the brace. Such braces lack a secure connection to the joists and will detach from the joist if the joists warp so that the compression they provide upon the brace no longer exists.
U.S. Pat. No. 4,246,736 discloses a one piece bracing system of fixed length. Since the brace attaches only to the topmost section of each joist, it is less able to brace against joist twisting.
U.S. Pat. No. 4,794,746 discloses a bracing system of fixed length. The problem with fixed length braces is that if the joists are not spaced apart a distance equal to the length of the brace, the brace will either be too long to fit between the joists or be too short to adequately support the joists.
U.S. Pat. No. 5,301,486 discloses a cross brace that uses wooden components, each of which requires precise cuts to be made in order for the components to fit. Constructing such a brace would be costly and time consuming. As mentioned earlier, wood braces have a number of problems that make them less than optimal as bracing members.
Thus, there is a need for an inexpensive, strong, adjustable and easily installable joist bracing apparatus. There is also a need for a bracing apparatus that reduces bounce and vibration in floor systems such as I-joist supported floors. The present invention meets these criteria.